Fastening Member and Electrical Connection Unit

Embodiments of the present invention relate to a fastening member and an electrical connection unit.

Priority is claimed on Japanese Patent Application No. 2024-175909 filed in Japan on Oct. 7, 2024, the content of which is incorporated herein by reference.

An electrical connection unit having an electronic component and a bus bar electrically connected to the electronic component is known.

[Patent Document 1]: Japanese Unexamined Patent Application, First Publication No. 2024-037492

Incidentally, it is expected to improve thermal characteristics of an electrical connection unit.

An embodiment provides a fastening member and an electrical connection unit capable of improving thermal characteristics.

A fastening member of one embodiment is used in an electrical connection unit. The fastening member includes a shaft, a base portion, and a heat storage portion. The shaft is inserted into a first attachment hole of a first member and a second attachment hole of a second member in a state in which the first attachment hole and the second attachment hole overlap each other in a first direction. The shaft has a screw thread. When a direction intersecting the first direction is a second direction, a width of the base portion in the second direction is larger than a width of the shaft. The base portion faces the first member or the second member in the first direction. The heat storage portion is provided on a side opposite to the shaft with respect to the base portion. The heat storage portion is formed integrally with the base portion.

An electrical connection unit according to an embodiment includes at least one of a first member and a second member, and a fastening member. The fastening member includes a shaft, a base portion, and a heat storage portion. The shaft is inserted into a first attachment hole of a first member and a second attachment hole of a second member in a state in which the first attachment hole and the second attachment hole overlap each other in a first direction. The shaft has a screw thread. When a direction intersecting the first direction is a second direction, a width of the base portion in the second direction is larger than a width of the shaft. The base portion faces the first member or the second member in the first direction. The heat storage portion is provided on a side opposite to the shaft with respect to the base portion. The heat storage portion is formed integrally with the base portion.

A fastening member of one embodiment is used in an electrical connection unit. The fastening member includes a first portion and a second portion. The first portion is inserted into a first attachment hole of a first member and a second attachment hole of a second member in a state in which the first attachment hole and the second attachment hole overlap each other in a first direction. The first portion has a screw thread and is engaged with a nut. When a direction intersecting the first direction is a second direction, a width of the second portion in the second direction is larger than a width of the first portion. The second portion faces the first member or the second member in the first direction. The second portion has a volume twice or more the volume of the nut.

An electrical connection unit according to an embodiment includes at least one of a first member and a second member, and a fastening member. The fastening member includes a first portion and a second portion. The first portion is inserted into a first attachment hole of a first member and a second attachment hole of a second member in a state in which the first attachment hole and the second attachment hole overlap each other in a first direction. The first portion has a screw thread and is engaged with a nut. In a case where a direction intersecting the first direction is a second direction, a width of the second portion in the second direction is larger than a width of the first portion. The second portion faces the first member or the second member in the first direction. The second portion has a volume twice or more the volume of the nut.

An electrical connection unit according to an embodiment includes a fastening member, a heat dissipation member, and a heat transfer member. The fastening member includes a first portion and a second portion. The first portion is inserted into a first attachment hole of a first member and a second attachment hole of a second member in a state in which the first attachment hole and the second attachment hole overlap each other in a first direction. The first portion has a screw thread. When a direction intersecting the first direction is a second direction, a width of the second portion in the second direction is larger than the first. The second portion faces the first member or the second member in the first direction. The heat dissipation member faces the second portion from a side opposite to the first member and the second member. The heat transfer member is disposed between the second portion and the heat dissipation member.

According to one embodiment, it is possible to improve thermal characteristics.

Hereinafter, embodiments will be described with reference to the drawings. In the following description, constitutions having the same or similar functions are denoted by the same reference numbers. Redundant descriptions of these constitutions may be omitted. Note that the constitution described below does not limit the scope of the embodiment.

In the present disclosure, the terms are defined as follows. The term “connection” is not limited to a mechanical connection, and may include an electrical connection. That is, the term “connection” is not limited to a case where two elements that are connection targets are directly connected, and may include a case where two elements that are connection targets are connected with another element interposed therebetween. The term “accommodation” is not limited to a case where the entire component is accommodated, and may include a case where only a part of the component is accommodated (a state in which the remaining part of the component protrudes). The term “facing” indicates that virtual projection images of two target objects overlap each other when viewed from a specific direction. That is, the term “facing” is not limited to a case where two target objects directly face each other, and may include a case where two target objects face each other in a state in which another member exists between the two target objects. “Parallel”, “orthogonal”, or “the same” may include “substantially parallel”, “substantially orthogonal”, or “substantially the same”, respectively.

110 1 110 2 110 110 3 110 4 110 110 e e e e 2 FIG. 2 FIG. 2 FIG. In the present disclosure, a +X direction, a −X direction, a +Y direction, a −Y direction, a +Z direction, and a −Z direction are defined as follows. The +X direction is a direction from a first endto a second endof a metal platethat will be described later (see). The −X direction is a direction opposite to the +X direction. Hereinafter, in a case where the +X direction and the −X direction are not distinguished, the directions will be simply referred to as “X direction”. The +Y direction and the −Y direction are directions intersecting (for example, orthogonal to) the X direction. The +Y direction is a direction from a third endto a fourth endof the metal platethat will be described later (see). The −Y direction is a direction opposite to the +Y direction. Hereinafter, in a case where the +Y direction and the −Y direction are not distinguished, the directions will be simply referred to as “Y direction”. The +Z direction and the −Z direction are directions intersecting (for example, orthogonal to) the X direction and the Y direction. The +Z direction is a direction from the metal platethat will be described later toward a main body MU (see). The −Z direction is a direction opposite to the +Z direction. Hereinafter, in a case where the +Z direction and the −Z direction are not distinguished, the directions will be simply referred to as “Z direction”. The Z direction is an example of a “first direction”. One of the X direction and the Y direction is an example of a “second direction”. The other of the X direction and the Y direction is an example of a “third direction”.

1 1 Hereinafter, in a case where the X direction and the Y direction are not distinguished, the directions may be referred to as “horizontal direction”. Hereinafter, the Z direction may be referred to as “vertical direction”. Hereinafter, the +Z direction side may be referred to as “upper”, and the −Z direction side may be referred to as “lower”. However, these expressions are expressions for convenience of description, and do not limit a gravity direction of an electrical connection unit(an installation posture of the electrical connection unit).

1 FIG. 1 1 1 1 is a cross-sectional view illustrating an electrical connection unitof an embodiment. The electrical connection unitis, for example, an in-vehicle device mounted on a vehicle such as an electric vehicle (EV), a hybrid electric vehicle (HEV), or a plug-in hybrid electric vehicle (PHEV). The electrical connection unitmay be referred to as an “electrical connection box” or a “junction box”, for example. However, the electrical connection unitis not limited to a box-shaped device.

1 5 110 119 120 2 FIG. 2 FIG. The electrical connection unitincludes, for example, a casing, a main body MU, a metal plate, a plurality of insulating covers(see), and a plurality of heat transfer members(see).

5 5 1 5 6 7 6 110 6 6 7 110 6 7 5 6 7 5 110 6 5 First, the casingwill be described. The casingforms an outline of the electrical connection unit. The casingincludes, for example, a baseand a cover. The baseis a member that covers the main body MU and the metal platefrom below. The basehas, for example, a plate shape formed in the horizontal direction or a bowl shape open in the +Z direction. The baseis made of, for example, a synthetic resin. The coveris a member that covers the main body MU and the metal platefrom above. The basehas, for example, a bowl shape open in the −Z direction. The coveris made of, for example, a synthetic resin. In the present embodiment, the box-shaped casingis formed by combining the baseand the cover. The shape of the casingis not limited to the above example. For example, the metal platethat will be described later may function as a part or the whole of the base. The casingmay be omitted.

1 1 2 1 1 10 2 2 10 10 10 1 10 10 In the present embodiment, the electrical connection unitincludes a first region (first space) Rand a second region (second space) R. The first region Ris a region in which a heat dissipation property is emphasized. In the first region R, for example, an electronic componentS having a great amount of heat generation is disposed. On the other hand, the second region Ris a region in which a mountability is emphasized. In the second region R, for example, an electronic componentT that has a smaller amount of heat generation than the electronic componentS and/or requires a more complicated mounting structure than the electronic componentS is disposed. However, these contents do not limit the contents of the electrical connection unitof the present disclosure. For example, the amount of heat generation of the electronic componentT may be greater than the amount of heat generation of the electronic componentS.

Next, the main body MU will be described.

2 FIG. 1 is a perspective view showing the main body MU. The main body MU is a portion that performs a main function (for example, switching of electrical connection states or overcurrent protection) of the electrical connection unit. In the present embodiment, the main body MU is divided into a plurality of subunits SU. The main body MU is formed by connecting the plurality of subunits SU, for example. In the present embodiment, the main body MU includes two subunits SU (subunit SUS and SUT). Each subunit SU may be referred to as a “circuit constitution body”.

10 40 10 40 41 The subunit SUS has an electrical first function. The subunit SUS includes, for example, a plurality of electronic componentsS and a routing boardS. The plurality of electronic componentsS are electrically connected to the routing boardS. The base plateS (that will be described later) included in the subunit SUS is an example of a “first base member”.

10 40 10 40 41 The subunit SUT has an electrical second function. The second function is, for example, a function different from the first function. The subunit SUT includes, for example, a plurality of electronic componentsT and a routing structureT. The plurality of electronic componentsT are electrically connected to the routing structureT. The base memberT (that will be described later) included in the subunit SUT is an example of a “second base member”.

1 1 110 In the present embodiment, the subunit SUS is a subunit SU in which a heat dissipation property is emphasized. The subunit SUS is disposed in the above first region Rof the electrical connection unit. The subunit SUS faces a first region Al of the metal platethat will be described later in the Z direction.

2 1 2 110 10 10 10 On the other hand, the subunit SUT is a subunit SU in which the mountability is emphasized. The subunit SUT is disposed, for example, on the +Y direction side with respect to the subunit SUS. The subunit SUT is disposed in the above second region Rof the electrical connection unit. The subunit SUT faces a second region Aof the metal platethat will be described later in the Z direction. Hereinafter, in a case where the electronic componentS and the electronic componentT are not distinguished, the electronic components are simply referred to as “electronic component”.

41 40 41 40 Note that the main body MU need not be divided into a plurality of subunits SU instead of the example described above. For example, the plurality of subunits SU may be integrally formed. For example, a base plateS of the routing boardS and a base memberT of the routing structureT, which will be described later, may be integrally formed by one piece member.

Next, a constitution of the subunit SUS will be described.

3 FIG. 10 20 40 20 20 is a perspective view showing the subunit SUS. The subunit SUS includes, for example, a plurality of electronic components, a plurality of connection components, and a routing boardS. The connection componentis a member forming an energization path in the vertical direction. The connection componentmay be referred to as a “vertical routing member”.

10 10 10 10 10 First, the electronic componentwill be described. The electronic componentis an electronic component mounted according to a function required for each subunit SU. The electronic componentis, for example, a connector, a fuse, a relay (for example, a mechanical relay or a semiconductor relay), a capacitor, a branch component, any of various sensors (for example, a current sensor or a voltage sensor), an electronic control unit, or an electronic component unit in which two or more of these are unitized. However, the type of the electronic componentis not limited to the above example. The electronic componentis, for example, a heat generating component that generates heat at the time of energization.

10 10 10 10 In the present embodiment, the plurality of electronic componentsinclude an electronic componentS that generates relatively large heat when energized. The electronic componentS is a relay (for example, a mechanical relay or a semiconductor relay), a pyrofuse, a current sensor (for example, a current sensor having a shunt resistor), or the like. However, the type of the electronic componentS is not limited to the above example.

4 FIG. 10 20 10 13 10 10 11 12 13 14 is a perspective view illustrating the electronic componentand the connection component. The electronic componentis, for example, an electronic component in which a plurality of terminalsare disposed to be arranged at one end of the electronic component. The electronic componentincludes, for example, a case, a component body, a plurality of terminals, and a plurality of the attachment portions.

11 10 11 11 12 11 12 The caseis an outer member that forms most of the outer shape of the electronic component. The caseis made of, for example, synthetic resin and has an insulating property. The caseaccommodates the component body. The caseand the component bodymay be integrally formed.

12 10 10 12 10 12 10 12 The component bodyis a portion that performs a main function of the electronic component. For example, in a case where the electronic componentis a relay, the component bodyincludes a switch (for example, a contact) that switches between a conductive state and a non-conductive state. For example, in a case where the electronic componentis a fuse, the component bodyincludes a fusion portion that is fused when an overcurrent flows. For example, in a case where the electronic componentis a capacitor, the component bodyincludes a portion that stores electric charge.

13 11 13 12 11 10 13 13 13 13 13 13 13 13 13 13 13 The terminalis an electrical connection portion exposed to the outside of the case. The terminalis electrically connected to the component bodyinside the case. In the present embodiment, the electronic componentincludes a terminalA and a terminalB as the plurality of terminals. One of the terminalA and the terminalB is a terminal on the positive electrode side. The other of the terminalA and the terminalB is a terminal on the negative electrode side. One of the terminalA and the terminalB is an example of a “first terminal”. The other of the terminalA and the terminalB is an example of a “second terminal”.

13 13 10 13 13 13 13 13 13 71 13 13 10 h h h In the present embodiment, the terminalA and the terminalB are provided at one end of the electronic componentin the horizontal direction (for example, the Y direction). The terminalA and the terminalB are disposed to be arranged in the horizontal direction (for example, the X direction). Each of the terminalA and the terminalB is directed in the horizontal direction (for example, the Y direction). Each terminalhas an attachment holeto which a fastening member(for example, a screw or a bolt) that will be described later is attached. The attachment holeis open in the horizontal direction (for example, the Y direction). An inner circumferential surface of the attachment holeof the electronic componenthas a screw groove. In the present disclosure, the “attachment hole” is not limited to a hole having a screw groove, and may be a hole not having a screw groove. In the present disclosure, the “attachment hole” is not limited to a bottomed hole, and may be a through-hole.

14 10 14 14 116 14 14 116 14 h h h 8 FIG. The attachment portionis a portion for fixing the electronic component. The attachment portionhas an attachment holeto which a fastening member(for example, a screw or a bolt; and see) that will be described later is attached. The attachment holeis open in the Z direction. The attachment holeis an insertion hole through which the fastening memberpasses. A fixing destination of the attachment portionwill be described later.

20 20 10 40 20 20 20 Next, the connection componentwill be described. The connection componentis a component that electrically connects the electronic componentto the routing boardS. The connection componentforms a part of an energization path in the subunit SUS. The connection componentis made of metal (for example, made of copper, made of a copper alloy, made of aluminum, or made of an aluminum alloy). The connection componentmay be referred to as a “metal component”.

20 10 42 40 12 20 10 11 10 3 FIG. In the present embodiment, the connection componentelectrically connects the electronic componentto the bus bar(see) included in the routing boardS. In the present embodiment, a length Lof the connection componentin the longitudinal direction (for example, the Y direction) of the electronic componentis smaller than a length Lof the electronic componentin the longitudinal direction.

20 21 22 The connection componentincludes, for example, a first portionand a second portion.

21 20 13 10 21 21 10 21 40 42 21 10 21 13 10 13 10 The first portionof the connection componentis a portion connected to the terminalof the electronic componentS. The first portionis a plate-shaped or rectangular parallelepiped portion extending in the Z direction. The first portionextends in the Z direction along one end (for example, an end in the Y direction) of the electronic component. The first portionis a standing portion that stands in the Z direction with respect to the routing boardS (for example, with respect to a bus barthat will be described later). The first portionis adjacent to the electronic componentin the horizontal direction (for example, the Y direction). For example, the first portionis adjacent to the terminalof the electronic componentin the horizontal direction (for example, the Y direction), and is connected to the terminalof the electronic componentfrom the horizontal direction (for example, the Y direction).

21 20 21 71 21 71 21 13 13 10 21 13 10 h h h h The first portionof the connection componenthas a first attachment holethrough which the fastening member(for example, a screw or a bolt) passes. The first attachment holeis open in the horizontal direction (for example, the Y direction). The fastening memberthat has passed through the first attachment holeis engaged with the attachment holeof the terminalof the electronic component, and thus the first portionis physically and electrically connected to the terminalof the electronic component.

22 20 42 22 21 22 22 42 42 22 20 43 42 42 22 20 22 43 22 22 43 22 44 43 22 22 42 21 22 20 3 FIG. 8 FIG. 3 FIG. h h h h The second portionof the connection componentis a portion connected to the bus bar(see). The second portionprotrudes in the horizontal direction (for example, the Y direction) from the end of the first portionon the −Z direction side. The second portionis a plate portion provided in the horizontal direction. The second portionis adjacent to the bus barin the Z direction, and is connected to the bus barfrom the Z direction. The second portionof the connection componentis attached to the fastening member(for example, a screw or a bolt; and see) protruding from the bus barin the +Z direction from the Z direction, and is physically and electrically connected to the bus bar. In the present embodiment, the second portionof the connection componenthas a second attachment holethrough which the fastening memberpasses. The second attachment holeis open in the Z direction. In the second portion, the fastening memberpasses through the second attachment hole. An engagement member(for example, a nut; and see) is engaged with the tip of the fastening memberthat has passed through the second attachment hole, and thus the second portionis fixed to the bus bar. In the present embodiment, the first portionand the second portionform one L-shaped connection component.

42 13 10 20 10 42 20 13 10 42 In the present embodiment, the bus baris disposed at a position away from the terminalof the electronic component(for example, a position away in the Z direction). The connection componentis disposed between the electronic componentand the bus bar. In the present disclosure, the phrase “the connection component is disposed between the electronic component and the bus bar” is not limited to a case where a part of the connection component is located between the electronic component and the bus bar when viewed from the X direction or the Y direction. The phrase “the connection component is disposed between the electronic component and the bus bar” may correspond to a case where a part of the connection component is located between the electronic component and the bus bar when viewed from a direction inclined with respect to the X direction or the Y direction. The connection componentelectrically connects the terminalof the electronic componentto the bus bar.

40 Next, the routing boardS will be described.

5 FIG. 40 40 10 10 10 10 10 40 is a perspective view showing the routing boardS. The routing boardS is a member that forms at least a part of an energization path between a plurality of electronic components(for example, a plurality of electronic componentsS) and/or at least a part of an energization path between the electronic component(for example, the electronic componentS) included in the subunit SUS and the electronic componentincluded in another subunit SU (for example, the subunit SUT). In the present disclosure, the “routing board” indicates a board-type routing structure. The “board type” indicates a plate shape along one plane when viewed as a whole regardless of a fine shape. In the present disclosure, the term “plate shape”, “sheet shape”, or “planar” is not limited to the case of being completely flat, and may include a case where a fixing structure, a rib, or the like protruding in the Z direction is partially present, a case where an uneven shape following the thickness of the bus bar is present on the surface, and the like. In the present embodiment, the routing boardS has a plate shape formed in the X direction and the Y direction.

40 41 42 43 41 42 40 42 41 43 42 42 41 40 The routing boardS includes, for example, a base plateS, one or more (for example, a plurality of) bus bars, and a plurality of fastening members. In the present embodiment, the base plateS and the plurality of bus barsare integrated through insert molding. For example, the routing boardS is formed as one piece member by insert-molding the bus barwith the base plateS after the fastening memberis fixed to the bus bar. That is, the bus baris integrated with the base plateS without using a fastening member such as a screw or a bolt. Note that the routing boardS may be formed by using another structure instead of the insert molding.

6 FIG. 40 41 42 43 40 is a partially exploded perspective view illustrating the routing boardS. Hereinafter, for convenience of description, the base plateS, the bus bar, and the fastening memberwill be described with reference to the drawings in which the routing boardS is partially exploded.

41 42 41 41 42 41 41 41 51 52 53 8 FIG. The base plateS is a support member that integrally supports the plurality of bus barsarranged at intervals in the horizontal direction. The base plateS is made of, for example, a synthetic resin and has an insulating property. The base plateS electrically insulates the plurality of bus barsfrom each other. The base plateS is an example of a “base member”. The base plateS may be referred to as an “insulating substrate”. The base plateS includes, for example, a flat surface portion, a frame portion, and a plurality of fixing portions(see).

51 41 51 51 41 51 41 51 41 41 52 41 The flat surface portionis a portion formed in a plate shape in the base plateS. The flat surface portionhas a plate shape formed in the horizontal direction. The flat surface portionforms a main portion of the base plateS. The flat surface portionforms a base portion (insulating base portion) of the base plateS. In the present embodiment, the flat surface portionextends over the entire width in the X direction of the base plateS and over the entire width in the Y direction of the base plateS except for the frame portionof the base plateS.

51 51 51 51 51 51 10 10 51 51 51 51 51 110 51 11 51 1 42 42 11 51 1 42 1 42 a b a a a b a b b b p 7 FIG. 2 FIG. 7 FIG. The flat surface portionhas a first surfaceand a second surface(see). The first surfaceis a surface directed in the +Z direction. The first surfaceis a flat surface provided in the horizontal direction. The first surfacefaces the plurality of electronic components(for example, the plurality of electronic componentsS). The second surfaceis located on the side opposite to the first surface. The second surfaceis a surface directed in the−Z direction. The second surfaceis a flat surface provided in the horizontal direction. The second surfacefaces the metal plate(see). A thickness direction (plate thickness direction) of the flat surface portionis the Z direction. In the present embodiment, a thickness Tof the flat surface portionin the Z direction is smaller than a thickness Tof the bus barin the Z direction (for example, a thickness of a horizontal plate portionthat will be described later in the Z direction) (see). The thickness Tof the flat surface portionin the Z direction may be equal to the thickness Tof the bus barin the Z direction, or may be larger than the thickness Tof the bus barin the Z direction.

51 55 42 55 55 51 55 51 51 51 55 51 55 41 41 55 55 51 41 41 55 42 a b The flat surface portionhas, for example, one or more (for example, a plurality of) accommodation portionsin which the bus barsare accommodated, respectively. The plurality of accommodation portionsare formed apart from each other in the X direction or the Y direction. Each of the accommodation portionsis, for example, a through-hole penetrating the flat surface portionin the Z direction. Note that the accommodation portionmay be a recess provided on the first surfaceor the second surfaceof the flat surface portionand recessed in the Z direction, instead of a through-hole. In the present disclosure, the phrase “the accommodation portion penetrates the flat surface portion in the first direction (Z direction)” may include a case where a part of the entire length of the accommodation portionpenetrates the flat surface portionin the Z direction (for example, the remaining portion of the accommodation portionmay be a recess recessed in the Z direction, or may be provided inside the base plateS and not exposed to the outside of the base plateS). Similarly, in the present disclosure, the phrase “the accommodation portion is recessed in the first direction (Z direction)” may include a case where a part of the entire length of the accommodation portionis recessed in the Z direction (for example, a remaining portion of the accommodation portionmay be a through-hole penetrating the flat surface portionin the Z direction, or may be provided inside the base plateS and not exposed to the outside of the base plateS). Each accommodation portionhas an outer shape corresponding to the shape of the bus barto be accommodated when viewed from the Z direction.

52 41 52 51 11 52 12 10 52 7 FIG. 7 FIG. The frame portionis provided at a peripheral end of the base plateS. The frame portionis a reinforcement rib protruding vertically from the end of the flat surface portion(see). A width (thickness) Hof the frame portionin the Z direction is, for example, less than half of a width (thickness) Hof the electronic componentin the Z direction (see). Note that the frame portionmay be omitted.

53 110 53 53 41 115 53 8 FIG. h h The fixing portionis a portion fixed to the metal plate(see). The fixing portionhas an attachment holepenetrating the base plateS in the Z direction. A fastening member(for example, a screw or a bolt) that will be described later passes through the attachment hole. This content will be described later.

42 40 42 10 42 10 10 10 42 The bus baris a routing member (electrical connection member) included in the routing boardS. The bus baris, for example, a routing member for electrically connecting a plurality of electronic components (for example, a plurality of electronic componentsS). Alternatively, the bus barmay be a routing member for electrically connecting the electronic component(for example, the electronic componentS) to the electronic componentincluded in another subunit SU (for example, the subunit SUT). The bus baris made of metal (for example, made of copper, made of a copper alloy, made of aluminum, or made of an aluminum alloy) and has conductivity.

42 42 55 51 42 51 51 42 55 42 42 42 42 42 42 61 62 63 a p p At least a part of each bus barhas a plate shape formed in the horizontal direction. At least a part of each bus baris accommodated in the accommodation portionand extends along the flat surface portion. That is, at least a part of each bus barextends along the first surfaceof the flat surface portion. At least a part of each bus barextends in the horizontal direction in the accommodation portion. Hereinafter, a portion of each bus barextending in a plate shape formed in the horizontal direction may be referred to as a “horizontal plate portion”. The horizontal plate portionis an example of a “plate portion”. The bus baris a member that forms a horizontal energization path. The bus barmay be referred to as a “horizontal routing member”. Each bus barincludes, for example, a connection portion, a connection portion, and an extending portion.

61 42 42 61 10 10 20 61 20 61 20 20 61 13 10 13 10 The connection portionis located in the middle of the bus baror at the first end of the bus bar. The connection portionis a portion connected to the electronic component(for example, the electronic componentS) directly or via the connection component. The connection portionincludes, for example, a portion overlapping the connection componentwhen viewed from the Z direction. The connection portionis adjacent to the connection componentin the Z direction and is connected to the connection componentfrom the Z direction. Instead of the above example, for example, the connection portionmay be adjacent to the terminalof the electronic componentin the Z direction and directly connected to the terminalof the electronic componentfrom the Z direction.

62 42 42 62 10 20 The connection portionis located in the middle of the bus baror at the second end of the bus bar. The connection portionis a portion connected to another electronic componentdirectly or via another connection component.

62 42 42 76 2 FIG. Instead of the above example, the connection portionmay be connected to another bus bar(for example, the bus barincluded in another subunit SU) or an external connection bus bar(see).

63 61 63 61 62 63 61 62 63 61 62 The extending portionextends from the connection portionin the X direction or the Y direction. The extending portionis provided between the connection portionand the connection portion. The extending portionextends over the connection portionand the connection portion. The extending portionconnects the connection portionto the connection portion.

42 61 63 61 63 55 p In the present embodiment, the horizontal plate portiondescribed above includes at least the entire connection portionand a part of the extending portion. That is, at least the entire connection portionand a part of the extending portionare accommodated in the accommodation portionand located on the same plane.

43 Next, the fastening memberwill be described.

7 FIG. 3 FIG. 7 7 43 42 20 42 43 42 43 is a cross-sectional view taken along line F-Fof the structure illustrated in. The fastening memberis a component for fixing the bus barto the connection componentcorresponding to the bus bar. The fastening memberis, for example, a caulking bolt fixed to the bus bar. The fastening memberis an example of a “fastening portion”.

61 62 42 42 42 42 43 43 43 43 43 43 43 43 42 43 42 42 43 42 43 42 42 43 42 h h a b a b a b a h a h In the present embodiment, at least one of the connection portionand the connection portionof the bus barhas an attachment hole. The attachment holeis, for example, a through-hole penetrating the bus barin the Z direction. The fastening memberis, for example, a bolt having a shaftand a head. A circumferential surface of the shafthas a screw groove. The headhas a diameter larger than that of the shaft. The headof the fastening memberis caulked and fixed to the bus barin a state in which the shaftpasses through the attachment holeof the bus bar. With this fixation, the fastening memberis electrically and physically connected to the bus barin a state in which the shaftprotrudes in the +Z direction from the attachment holeof the bus bar. The fastening memberis not limited to caulking fixation, and may be fixed to the bus barthrough welding or other methods.

20 43 10 71 20 43 43 22 22 44 43 43 22 22 20 44 43 22 20 43 a h a h a In the present embodiment, the connection componentis attached to the fastening memberfrom the Z direction in a state of being previously fixed to the electronic componentvia the fastening member. For example, in the connection component, the shaftof the fastening memberis inserted into the second attachment holeof the second portion. The engagement member(for example, a nut) is engaged with the shaftof the fastening memberprotruding from the second attachment holeof the second portionof the connection component. The engagement memberis attached to the shaftin the Z direction. This engagement fixes the second portionof the connection componentto the fastening member.

120 120 10 10 42 110 120 120 41 41 120 120 First, the heat transfer memberwill be described. The heat transfer memberis a member for transferring heat generated by the electronic component(for example, the electronic componentS) at the time of energization and/or heat (Joule heat) generated by the bus baritself at the time of energization to the metal plate. The heat transfer memberis, for example, a heat transfer sheet (for example, a thermally conductive silicone sheet) having elasticity. The heat transfer memberis made of a material having a higher thermal conductivity than the base plateS (or the base memberT that will be described later), for example. However, the heat transfer memberis not limited to the above example, and may be a heat transfer member formed of a thermally conductive gel or another material. In the present embodiment, the heat transfer memberhas an insulating property.

120 40 120 42 120 42 111 110 120 42 42 111 110 42 42 111 110 120 10 10 42 42 42 111 110 2 FIG. u u In the present embodiment, the heat transfer memberis partially provided in the routing boardS (see). For example, the heat transfer memberis disposed at a position overlapping a part of the bus barwhen viewed from the Z direction. The heat transfer memberis disposed between the bus barand a flat surface portionof the metal platethat will be described later. For example, the heat transfer memberis disposed between the exposed portionof the bus barand the flat surface portionof the metal plate, and is in contact with the exposed portionof the bus barand the flat surface portionof the metal plate. The heat transfer membertransfers heat transferred from the electronic component(for example, the electronic componentS) to the bus barand/or heat generated by the bus barfrom the bus barto the flat surface portionof the metal plate.

120 42 10 10 120 20 120 61 62 42 120 10 42 20 42 111 110 In the present embodiment, the heat transfer memberis disposed at a position overlapping a part of the bus barin the vicinity of the electronic component(for example, the electronic componentS) when viewed from the Z direction. In the present embodiment, the heat transfer memberis disposed at a position overlapping the connection componentwhen viewed from the Z direction. In other words, the heat transfer memberis disposed at a position overlapping the connection portionor the connection portionof the bus barwhen viewed from the Z direction. The heat transfer membertransfers heat transferred from the electronic componentS to the bus barvia the connection componentfrom the bus barto the flat surface portionof the metal plate.

40 10 Next, a fixing structure of the routing boardS and the electronic componentwill be described.

8 FIG. 3 FIG. 8 8 110 112 113 111 is a cross-sectional view taken along line F-Fof the structure illustrated in. The metal plateincludes, for example, a fixing portionand a fixing portionin addition to a flat surface portionthat will be described later.

112 41 110 112 53 41 112 111 110 112 112 112 h h The fixing portionis a fixing portion for fixing the base plateS to the metal plate. The fixing portionis provided at a position corresponding to the fixing portionof the base plateS when viewed from the Z direction. The fixing portionis a cylindrical or prismatic boss protruding in the +Z direction from the flat surface portionof the metal plate. The fixing portionhas an engagement holethat is open in the +Z direction. An inner circumferential surface of the engagement holehas a screw groove.

53 41 53 115 53 115 53 53 41 112 112 110 41 110 h h h h As described above, the fixing portionof the base plateS has an attachment hole. A fastening member(for example, a screw or a bolt) passes through the attachment hole. When the fastening memberthat has passed through the attachment holeof the fixing portionof the base plateS is engaged with the engagement holeof the fixing portionof the metal plate, the base plateS is fixed to the metal plate.

113 10 10 110 41 113 14 10 113 111 113 113 113 h h The fixing portionis a fixing portion for directly fixing the electronic component(for example, the electronic componentS) to the metal platewithout the base plateS interposed therebetween. The fixing portionis provided at a position corresponding to the attachment portionof the electronic componentwhen viewed from the Z direction. The fixing portionis a cylindrical or prismatic boss protruding in the +Z direction from the flat surface portion. The fixing portionhas an engagement holethat is open in the +Z direction. An inner circumferential surface of the engagement holehas a screw groove.

51 41 51 51 51 51 113 110 113 110 51 41 51 51 51 51 14 10 113 51 51 51 51 h. h h h a a a a In the present embodiment, the flat surface portionof the base plateS has a through-holeThe through-holepenetrates the flat surface portionin the Z direction. The through-holeis provided at a position corresponding to the fixing portionof the metal platewhen viewed from the Z direction. The fixing portionof the metal platepasses through the through-holeof the base plateS and protrudes to the same position as the first surfaceof the flat surface portionor further toward the +Z direction side than the first surfaceof the flat surface portion. The attachment portionof the electronic componentis in contact with the fixing portionat the same position as the first surfaceof the flat surface portionor at a position located further toward the +Z direction side than the first surfaceof the flat surface portion.

116 14 14 10 116 14 14 10 113 113 110 10 110 41 10 41 h h h A fastening member(for example, a screw or a bolt) passes through the attachment holeof the attachment portionof the electronic componentfrom the +Z direction side. When the fastening memberthat has passed through the attachment holeof the attachment portionof the electronic componentis engaged with the engagement holeof the fixing portionof the metal plate, the electronic componentis fixed to the metal platewithout the base plateS interposed therebetween. Note that, instead of the above-described example, the electronic componentmay be fixed to a fixing portion provided in the base plateS.

Next, a constitution of the subunit SUT will be described.

9 FIG. 13 FIG. 10 40 101 is a perspective view illustrating the subunit SUT. The subunit SUT includes, for example, a plurality of electronic components, a routing structureT, and an auxiliary base member(see).

10 10 10 10 10 10 10 9 FIG. 9 FIG. First, the electronic componentwill be described. The plurality of electronic componentsinclude a plurality of electronic componentsTA (only one is illustrated in) and a plurality of electronic componentsTB (only one is illustrated in). Note that the plurality of electronic componentsmay include only one of the electronic componentTA and the electronic componentTB.

10 10 10 10 10 10 10 10 10 13 111 110 10 10 10 10 13 FIG. The electronic componentTA is an example of the electronic componentT described above. The electronic componentTA is an electronic component having a smaller amount of heat generation than the electronic componentS when energized. On the other hand, the electronic componentTB is another example of the electronic componentT described above. The electronic componentTB is an electronic component having a lower mountability (for example, requiring a complicated implementation structure) than the electronic componentS. The electronic componentTB has, for example, a terminalprotruding in the −Z direction toward the flat surface portionof the metal plate(see). For example, the electronic componentTB has a smaller amount of heat generation than the electronic componentS when energized. As described above, the amount of heat generation of the electronic componentT may be greater than the amount of heat generation of the electronic componentS.

10 10 10 10 10 Hereinafter, in a case where the electronic componentTA and the electronic componentTB are not distinguished, the electronic components are simply referred to as “electronic componentT”. The electronic componentT is, for example, a connector, a fuse, a capacitor, a branch component, any of various sensors (for example, a current sensor or a voltage sensor), an electronic control unit, or an electronic component unit in which two or more of these are unitized. However, the type of the electronic componentT is not limited to the above example.

10 FIG. 10 10 13 10 13 13 10 13 13 11 13 13 13 43 90 13 13 13 13 h h h h is a front view illustrating the electronic componentTA. The electronic componentTA is, for example, an electronic component in which a plurality of terminalsare separately disposed at both ends of the electronic componentTA in the horizontal direction. In the present embodiment, the terminalA and the terminalB are disposed separately at both ends of the electronic componentTA in the Y direction. The terminalsA andB protrude in the horizontal direction (for example, the +Y direction or the −Y direction) from the center of the casein the Z direction. Each terminalis, for example, a plate portion provided in the horizontal direction. Each terminalhas an attachment holethrough which a fastening member(for example, a screw or a bolt) or a fastening memberthat will be described later passes. The attachment holeis open in the Z direction. An inner circumferential surface of the attachment holehas no screw groove. The attachment holeis a through-hole penetrating the terminalin the Z direction.

9 FIG. 40 40 10 10 10 10 10 40 41 42 43 90 43 43 Next, referring toagain, the routing structureT will be described. The routing structureT is a member that forms at least a part of an energization path between the plurality of electronic components(for example, the plurality of electronic componentsT) and/or at least a part of an energization path between the electronic component(for example, the electronic componentT) included in the subunit SUT and the electronic componentincluded in another subunit SU (for example, the subunit SUS). The routing structureT includes, for example, a base memberT, one or more (for example, a plurality of) bus bars, a plurality of fastening members, and a fastening memberhaving a heat storage function. Note that the content of the fastening memberis similar to that of the fastening memberdescribed in the subunit SUS, and thus repeated description will be omitted.

11 FIG. 41 41 42 41 41 42 41 41 41 41 81 85 87 is a perspective view illustrating the base memberT. The base memberT is a support member that integrally supports the plurality of bus barsarranged at intervals in the horizontal direction. The base memberT is made of, for example, a synthetic resin and has an insulating property. The base memberT electrically insulates the plurality of bus barsfrom each other by using, for example, a rib (not illustrated). The base memberT may be referred to as an “insulating substrate”. The base memberT has a three-dimensional structure thicker in the Z direction than the base plateS included in the subunit SUS. The base memberT includes, for example, a support wall, a frame portion(peripheral wall portion), and a fixing portion.

81 42 81 81 81 42 43 90 81 43 90 81 9 FIG. The support wallis, for example, a plate-shaped wall portion provided in the horizontal direction. The plurality of bus barsare disposed on the support walland are supported from below by the support wall(see). The support wallthat supports the bus baris not limited to a wall portion provided in the horizontal direction, and may be a grid-shaped wall portion formed by a plurality of ribs extending in the Z direction. In the present embodiment, the fastening memberand the fastening memberare attached to the support wall. The fastening memberand the fastening memberprotrude from the support wallin the +Z direction.

41 84 84 81 81 84 11 12 10 10 10 10 12 84 10 84 81 In the present embodiment, the base memberT has an accommodation portionA that is open to the +Z direction side. The accommodation portionA is, for example, a recess in which a part of the support wallis recessed in the Z direction or a through-hole penetrating the support wallin the Z direction. The accommodation portionA has an outer shape corresponding to the shape of the case(that is, the component body) of the electronic component(for example, the electronic componentT) when viewed from the Z direction. At least a part of the electronic component(for example, the electronic componentT) (for example, at least a part of the component body) is accommodated in the accommodation portionA. At least a part of the electronic componentaccommodated in the accommodation portionA is located on the −Z direction side compared with the support wall.

85 41 85 41 21 85 22 10 10 85 13 FIG. The frame portionis provided at a peripheral end of the base memberT. The frame portionis a rib (peripheral wall portion) extending in the Z direction at the peripheral end of the base memberT. A width (thickness) Hof the frame portion(peripheral wall portion) in the Z direction is, for example, half or more of a width (thickness) Hof the electronic component(for example, the electronic componentTA) in the Z direction (see). Note that the frame portionmay be omitted.

87 110 87 112 110 87 87 41 115 87 115 87 112 112 110 41 110 13 FIG. h h h h The fixing portionis a portion fixed to the metal plate(see). The fixing portionfaces the fixing portionof the metal platein the Z direction. The fixing portionhas an attachment holepenetrating the base memberT in the Z direction. A fastening member(for example, a screw or a bolt) passes through the attachment hole. When the fastening memberthat has passed through the attachment holeis engaged with the engagement holeof the fixing portionof the metal plate, the base memberT is fixed to the metal plate.

42 40 Next, the bus barincluded in the routing structureT will be described.

12 FIG. 15 FIG. 42 40 42 10 10 42 10 10 10 42 41 110 42 13 10 42 12 10 is a plan view illustrating the subunit SUT. The bus baris a routing member (electrical connection member) included in the routing structureT. The bus baris, for example, a routing member for electrically connecting a plurality of electronic components(for example, a plurality of electronic componentsT). Alternatively, the bus barmay be a routing member for connecting the electronic component(for example, the electronic componentT) to the electronic componentincluded in another subunit SU (for example, the subunit SUS). In the present embodiment, the plurality of bus barsare supported from below by the base memberT and are disposed at positions away from the metal plate. The bus baris disposed immediately below the terminalof the electronic component, for example. The bus baroverlaps the component bodyof the electronic componentwhen viewed from the X direction or the Y direction (see).

42 42 42 42 42 42 42 42 42 42 42 42 42 42 42 42 42 42 61 62 63 10 10 p p The plurality of bus barsinclude, for example, four bus barsE,F,G, andI. The four bus barsE,F,G, andI are disposed to be arranged at intervals in the horizontal direction. The four bus barsE,F,G, andI include portions disposed on the same plane. At least a part of each bus baris the horizontal plate portion. In the present embodiment, each bus barhas a plate shape formed in the horizontal direction over the entire length. The horizontal plate portionof each bus barincludes the connection portion, the connection portion, and the extending portion. In the present embodiment, the subunit SUT includes an electronic componentD as one of the electronic componentsTA.

61 42 42 61 42 42 62 42 13 10 13 10 42 42 62 42 p The connection portionof the bus barE is connected to the bus barincluded in the subunit SUS. Similarly, the connection portionof the bus barF is connected to the bus barincluded in the subunit SUS. The connection portionof the bus barF is physically and electrically connected to the terminalA of the electronic componentD. For example, the terminalA of the electronic componentD is placed on the horizontal plate portionof the bus barF to be connected to the connection portionof the bus barF.

61 42 13 10 13 10 42 42 61 42 61 42 62 42 76 62 42 76 62 42 76 62 42 13 10 76 p The connection portionof the bus barG is physically and electrically connected to the terminalB of the electronic componentD. For example, the terminalB of the electronic componentD is placed on the horizontal plate portionof the bus barG to be connected to the connection portionof the bus barG. The connection portionof the bus barG is an example of a “first connection portion”. The connection portionof the bus barG is physically and electrically connected to the external connection bus bar. The connection portionof the bus barG is connected to an external device via the bus bar. The connection portionof the bus barG is an example of a “second connection portion”. The bus baris an example of an “external connection component”. Note that the connection portionof the bus barG may be physically and electrically connected to the terminalof another electronic componentinstead of the bus bar.

61 42 42 62 42 13 10 The connection portionof the bus barI is connected to the bus barincluded in the subunit SUS. The connection portionof the bus barI is physically and electrically connected to the terminalA of the electronic componentT (not illustrated).

101 Next, the auxiliary base memberwill be described.

13 FIG. 12 FIG. 13 13 101 102 101 102 101 101 41 111 110 101 10 13 10 102 101 41 111 110 101 is a cross-sectional view taken along line F-Fof the structure illustrated in. The auxiliary base memberis made of, for example, a synthetic resin and has an insulating property. A plurality of wiringsare provided on the surface of the auxiliary base member. The wiringis, for example, a conductive layer (metal layer) provided on the surface of the auxiliary base member. The auxiliary base memberis disposed between the base memberT and the flat surface portionof the metal platein the Z direction. The auxiliary base memberfaces the electronic componentTB from the −Z direction side. The terminalof the electronic componentTB is electrically connected to the wiringprovided on the auxiliary base memberat a position between the base memberT and the flat surface portionof the metal plate. The auxiliary base memberis an example of a “third base member”.

90 Next, the fastening memberhaving a heat storage function will be described.

14 FIG. 90 90 43 90 90 90 is a perspective view showing the fastening member. The fastening memberhas a larger heat storage capacity than a general fastening member (for example, the fastening member), and is a fastening member that physically and electrically connects a plurality of members. The fastening memberis made of metal and has a conductivity. A material of the fastening memberis, but is not limited to, copper, a copper alloy, aluminum, an aluminum alloy, steel, stainless steel, magnesium, a magnesium alloy, titanium, a titanium alloy, or the like. The fastening membermay be referred to as a “heat storage member” or a “metal member”.

90 90 10 42 10 20 90 44 The fastening memberfastens the first member to the second member. For example, the fastening memberfastens the electronic componentto the bus bar. The electronic componentis an example of a “first member”. The connection componentis an example of a “second member”. In the present disclosure, the term “fasten” or “fix” is not limited to the case of fastening or fixing using a single component (fastening member), and may include the case of fastening or fixing in combination with another component (for example, the engagement membersuch as a nut).

10 20 10 42 76 10 20 10 42 76 90 42 42 76 20 10 42 The first member and the second member are not limited to the above example. For example, the first member is any one of the electronic component, a connection component (for example, the connection component) attached to the electronic component, the bus bar, or the external connection bus bar. For example, the second member is any one of the electronic component, a connection component (for example, the connection component) attached to the electronic component, the bus bar, or the external connection bus bar. For example, the fastening membermay fix the bus barto another bus bar(or the external connection bus bar), or fasten the connection componentattached to the electronic componentto the bus bar.

90 90 10 42 10 42 Hereinafter, as an example of the fastening member, the fastening memberthat fastens the electronic component(first member) to the bus bar(second member) will be described. However, in the following description, the terms “electronic component″ and ”bus bar″ may be appropriately replaced with different members on the basis of the gist described above.

14 FIG. 13 10 13 13 13 13 13 91 90 13 13 h h h h h h As illustrated in, the terminalof the electronic componenthas an attachment hole. The attachment holeis, for example, a through-hole penetrating the terminalin the Z direction. An inner circumferential surface of the attachment holehas no screw groove. However, as described above, the “attachment hole” in the present disclosure is not limited to a hole having no screw groove, and may be a hole having screw groove. In the present disclosure, the “attachment hole” is not limited to a through-hole, and may be a bottomed hole. For example, the attachment holemay be a hole having a screw groove and engaged with the shaftof the fastening member. The attachment holemay be a bottomed hole. The attachment holeis an example of a “first attachment hole”.

61 42 42 42 42 42 42 91 90 42 42 13 10 42 42 44 h h h h h h h h Similarly, the connection portionof the bus barhas an attachment hole. The attachment holeis, for example, a through-hole penetrating the bus barin the Z direction. An inner circumferential surface of the attachment holehas no screw groove. However, the attachment holemay be a hole having a screw groove and engaged with the shaftof the fastening member. The attachment holemay be a bottomed hole. The attachment holeis an example of a “second attachment hole”. In a case where one of the attachment holeof the electronic componentand the attachment holeof the bus baris a hole having a screw groove, the engagement membercan be omitted.

90 90 91 92 93 Next, a structure of the fastening memberwill be described. The fastening memberincludes, for example, a shaft, a base portion, and a heat storage portion.

91 91 91 13 10 42 42 13 10 42 42 91 13 10 42 42 45 44 h h h h h h The shaftis a cylindrical portion having a screw thread Sc on the outer circumferential surface. The shaftextends in the Z direction. The shaftis inserted into the attachment holeof the electronic componentand the attachment holeof the bus barin a state in which the attachment holeof the electronic componentand the attachment holeof the bus baroverlap each other in the Z direction. In the present embodiment, the tip of the shaftthat has passed through the attachment holeof the electronic componentand the attachment holeof the bus barpasses through a washer, and is engaged with the engagement member(for example, a nut).

92 91 92 2 92 1 91 2 92 13 13 10 2 92 42 42 42 92 13 10 42 92 13 10 42 h h h h The base portionis a portion thicker in the horizontal direction than the shaft. The base portionhas, for example, a flat cylindrical shape. A width W(for example, a diameter) of the base portionin the Y direction (or the X direction) is larger than a width W(for example, a diameter) of the shaftin the Y direction (or the X direction). A width W(for example, a diameter) of the base portionin the Y direction (or the X direction) is larger than a width W(for example, a diameter) of the attachment holeof the electronic componentin the Y direction (or the X direction). The width W(for example, a diameter) of the base portionin the Y direction (or the X direction) is larger than a width W(for example, a diameter) of the attachment holeof the bus barin the Y direction (or the X direction). The base portionis disposed on the −Z direction side with respect to the terminalof the electronic componentand the bus bar. The base portionfaces the terminalof the electronic componentor the bus barin the Z direction.

93 93 91 92 93 92 93 93 44 The heat storage portionis a portion provided to secure a large heat capacity. The heat storage portionis provided on the side opposite to the shaftwith respect to the base portion. The heat storage portionis formed integrally with the base portion. In the present embodiment, the heat storage portionis a solid cylindrical portion extending in the Z direction. In the present embodiment, the volume (heat capacity) of the heat storage portionis twice or more the volume (heat capacity) of the engagement member(for example, a nut).

93 92 3 93 2 92 92 93 3 93 2 92 92 93 3 93 1 91 In the present embodiment, the heat storage portionbulges in the horizontal direction with respect to the base portion. A width Wof the heat storage portionin the Y direction (or X direction) is larger than the width Wof the base portionin the Y direction (or X direction). With this structure, a step ST in the horizontal direction is formed between the base portionand the heat storage portion. However, the width Wof the heat storage portionin the Y direction (or the X direction) may be the same as the width Wof the base portionin the Y direction (or the X direction). That is, the step ST need not exist between the base portionand the heat storage portion. In the present embodiment, the width Wof the heat storage portionin the Y direction (or the X direction) is twice or more the width Wof the shaftin the Y direction (or the X direction).

3 93 2 92 3 93 2 92 93 111 110 42 90 111 110 In the present embodiment, a thickness Tof the heat storage portionin the Z direction is larger than a thickness Tof the base portionin the Z direction. For example, the thickness Tof the heat storage portionin the Z direction is twice or more the thickness Tof the base portionin the Z direction. The end of the heat storage portionon the −Z direction side is located near the flat surface portionof the metal platebeyond, for example, a midpoint in the Z direction between the bus barfastened by the fastening memberand the flat surface portionof the metal plate.

2 92 3 93 1 42 42 3 93 1 42 42 3 93 1 42 42 p p p 15 FIG. In the present embodiment, the sum of the thickness Tof the base portionin the Z direction and the thickness Tof the heat storage portionin the Z direction is larger than the thickness Tof the horizontal plate portionof the bus barin the Z direction (see). For example, the thickness Tof the heat storage portionin the Z direction is larger than the thickness Tof the horizontal plate portionof the bus barin the Z direction. For example, the thickness Tof the heat storage portionin the Z direction is twice or more the thickness Tof the horizontal plate portionof the bus barin the Z direction.

90 90 90 a b. From another viewpoint, the fastening memberincludes a first portionand a second portion

90 91 90 90 90 45 44 a a a a The first portionis a portion formed by the above-described shaft. The first portionis a cylindrical portion extending in the Z direction. The outer circumferential surface of the first portionhas a screw thread Sc. The first portionpasses through the washerand is engaged with the engagement member(for example, a nut).

90 92 93 90 90 44 b b b The second portionis a portion formed by the base portionand the heat storage portiondescribed above. The second portionis a cylindrical portion having the step ST and including an enlarged diameter portion. In the present embodiment, the volume (heat capacity) of the second portionis twice or more the volume (heat capacity) of the engagement member(for example, the nut).

13 10 90 13 10 Note that, instead of being provided to correspond to one terminalof the electronic component, the fastening membermay be provided to correspond to each of the two terminalsA of the electronic component. The same applies to modification examples and other embodiments described below.

15 FIG. 12 FIG. 15 15 41 88 93 88 88 88 a b. is a cross-sectional view taken along line F-Fof the structure illustrated in. In the present embodiment, the base memberT includes a holding portionthat holds the heat storage portion. The holding portionincludes, for example, a first portionand a second portion

88 42 13 10 93 88 92 88 92 93 88 93 93 a a a a The first portionis located between the bus bar(or the terminalof the electronic component) and the heat storage portionin the Z direction. The first portionis adjacent to the base portionin the X direction or the Y direction. The first portionfaces the step ST between the base portionand the heat storage portionin the Z direction. The first portionfaces the heat storage portionin the Z direction and supports the heat storage portionin the Z direction.

88 88 88 93 88 93 93 88 93 b a b b b The second portionis, for example, a tubular portion extending in the −Z direction from a peripheral edge of the first portion. The second portionfaces the heat storage portionin the X direction or the Y direction. The second portionsurrounds the heat storage portionalong the outer circumference of the heat storage portion. The second portionsupports the heat storage portionin the horizontal direction.

90 41 90 88 88 In the present embodiment, the fastening memberis formed integrally with the base memberT through insert molding. For example, the fastening memberis formed integrally with the holding portionthrough insert molding, and is supported by the holding portion.

93 91 111 110 110 93 13 42 10 120 93 111 110 120 93 111 110 120 93 111 110 120 93 111 110 In the present embodiment, the heat storage portionis located between the shaftand the flat surface portionof the metal plate. That is, the metal platefaces the heat storage portionfrom the side opposite to the terminalor the bus barof the electronic component. The heat transfer memberis disposed between the heat storage portionand the flat surface portionof the metal plate. The heat transfer memberis in contact with, for example, the heat storage portionand the flat surface portionof the metal plate. The heat transfer memberis sandwiched between the heat storage portionand the flat surface portionof the metal plateand elastically deformed. The heat transfer memberthermally connects the heat storage portionto the flat surface portionof the metal plate.

90 90 10 10 76 90 10 42 90 90 110 The fastening memberis, for example, a heat absorbing member that increases the heat capacity of the energization path included in the subunit SUT. For example, the fastening memberstores (absorbs) part of heat transferred from an external device to the electronic component(for example, the electronic componentT) via the external connection bus bar. Alternatively, the fastening membermay store (absorb) at least part of the heat generated by the electronic componentand/or at least part of the heat generated by the bus baritself. In a case where the fastening memberis used as a heat storage member (heat absorbing member), the fastening memberneed not be thermally connected to the metal plate.

90 10 10 76 111 110 90 13 10 76 10 42 90 10 In the present embodiment, the fastening memberalso functions as, for example, a heat transfer portion that transfers part of heat directed from an external device to the electronic component(for example, the electronic componentT) via the external connection bus barto the flat surface portionof the metal platethat will be described later. In the present embodiment, the fastening memberis provided to correspond to the terminalB of the electronic component. According to this structure, part of heat directed from the external connection bus barto the electronic componentthrough the bus bareasily moves to the fastening memberbefore reaching the electronic component.

90 10 42 111 110 111 110 42 111 110 42 111 110 Alternatively, the fastening membermay be a heat transfer portion that transfers at least part of heat generated by the electronic componentand/or at least part of heat generated by the bus baritself to the flat surface portionof the metal plate. The flat surface portionof the metal plateis disposed away from the bus barin the Z direction. The flat surface portionof the metal platefaces the bus barin the Z direction. The flat surface portionof the metal plateis an example of a “facing portion”.

90 Next, a modification example of the fastening memberwill be described. Note that constitutions other than those described below in the present modification example are the same as those of the first embodiment.

16 FIG. 16 FIG. 90 91 92 93 3 93 2 92 3 93 2 92 is a cross-sectional view illustrating a subunit SUT of a modification example. As in the first embodiment, the fastening memberincludes a shaft, a base portion, and a heat storage portion. In the example illustrated in, the thickness Tof the heat storage portionin the Z direction is substantially equal to the thickness Tof the base portionin the Z direction. However, also in the present modification example, the thickness Tof the heat storage portionin the Z direction may be larger than the thickness Tof the base portionin the Z direction as in the first embodiment.

17 FIG. 90 93 92 3 93 2 92 is a perspective view illustrating a fastening memberaccording to a modification example. Also in the present modification example, the heat storage portionbulges in the horizontal direction with respect to the base portion. A width Wof the heat storage portionin the Y direction (or X direction) is larger than the width Wof the base portionin the Y direction (or X direction).

92 93 92 93 93 93 93 93 93 93 90 93 a b a b In the present modification example, the base portionhas a perfect circle shape when viewed from the Z direction. On the other hand, the heat storage portionis larger than the base portionand has a shape different from a perfect circle or a regular polygon when viewed from the Z direction. For example, the heat storage portionincludes four straight portionsand four corner portionsprovided between the four straight portionswhen viewed from the Z direction. The corner portionhas an arc shape protruding outward in the horizontal direction. When viewed from the Z direction, the heat storage portionhas a shape having a larger area (volume) than a perfect circle having the same maximum width in the X direction and the Y direction as the heat storage portion. With this structure, the heat capacity of the fastening memberis further increased. The heat storage portionmay have a shape such as a regular polygon (for example, a regular square) when viewed from the Z direction.

2 FIG. 110 119 Next, referring toagain, the metal plateand the insulating coverwill be described.

110 1 1 110 110 110 The metal plateis a member that secures rigidity of the electrical connection unitand enhances the heat dissipation property of the electrical connection unit. The metal plateis made of metal (for example, aluminum or an aluminum alloy). The metal plateis an example of a “heat dissipation member”. The metal platemay be referred to as a “metal member” or a “rigid member”.

110 110 110 1 110 2 110 3 110 4 110 1 110 2 110 110 3 110 4 110 110 111 112 113 e e e e e e e e 8 FIG. 8 FIG. The metal platehas a rectangular shape formed in the X direction and the Y direction. The metal platehas a first end, a second end, a third end, and a fourth end. The first endand the second endare a pair of ends of the metal platein the longitudinal direction, and are separated in the X direction. The third endand the fourth endare a pair of ends of the metal platein the lateral direction, and are separated in the Y direction. The metal plateincludes, for example, the flat surface portion, the plurality of fixing portions(see) described above, and the plurality of fixing portions(see) described above.

111 110 111 111 110 111 110 111 The flat surface portionis a portion formed in a plate shape in the metal plate. The flat surface portionhas a plate shape formed in the horizontal direction. The flat surface portionforms a main portion of the metal plate. The flat surface portionforms a base portion (metal base portion) of the metal plate. The flat surface portionhas a size that covers the two subunits SU from below.

111 1 2 1 111 1 111 10 41 1 111 In the present embodiment, the flat surface portionhas a first region Aand a second region A. The first region Ais, for example, a region on the −Y direction side in the flat surface portion. The subunit SUS described above faces the first region Aof the flat surface portionwhen viewed from the Z direction. That is, the plurality of electronic componentsS and the base plateS included in the subunit SUS face the first region Aof the flat surface portionin the Z direction.

2 111 2 111 10 41 2 111 The second region Ais, for example, a region on the +Y direction side in the flat surface portion. The above-described subunit SUT faces the second region Aof the flat surface portionwhen viewed from the Z direction. That is, the plurality of electronic componentsT and the base memberT included in the subunit SUT face the second region Aof the flat surface portionin the Z direction.

119 119 119 119 119 119 119 119 h The insulating coveris a member for preventing the subunit SU from contacting the energization path. The insulating coveris made of, for example, a synthetic resin and has an insulating property. The insulating coverhas, for example, a box shape that is open on the −Z direction side. The insulating coverhas a plurality of vent holes. The insulating covercovers a part or the whole of the corresponding subunit SU. Note that the insulating coveris not limited to a box-shaped member, and may be a sheet-shaped member that covers the energization path of the main body MU. Further, the insulating covermay be omitted.

90 As a comparative example, a structure without the fastening memberwill be considered. In such a structure, in a case where a sufficient heat capacity is not ensured in the electrical connection unit, a large temperature rise may occur in a part of the electrical connection unit and/or thermal interference with the electronic component may increase. For example, when a transient large current flows, a large temperature rise may occur in a part of the electrical connection unit and/or thermal interference with the electronic component may increase. Therefore, it may be difficult to improve the thermal characteristics of the electrical connection unit.

1 90 90 91 92 93 91 13 10 42 42 91 92 91 92 93 91 92 93 92 h h In the present embodiment, the electrical connection unithas the fastening member. The fastening memberincludes the shaft, the base portion, and the heat storage portion. The shaftis inserted into the first attachment hole and the second attachment hole in a state in which the first attachment hole (for example, the attachment hole) of the first member (for example, the electronic component) and the second attachment hole (for example, the attachment hole) of the second member (for example, the bus bar) overlap each other in the first direction (Z direction). The shafthas the screw thread Sc. The width of the base portionin the X direction or the Y direction is larger than that of the shaft. The base portionfaces the first member or the second member in the Z direction. The heat storage portionis provided on the side opposite to the shaftwith respect to the base portion. The heat storage portionis formed integrally with the base portion.

90 42 90 1 10 1 1 According to such a constitution, the heat storage function (heat absorbing function) can be improved by using the member used as the fastening member. According to this constitution, part of heat transferred through the bus barcan be stored (absorbed) at least temporarily by the fastening member. According to this structure, it is possible to suppress the occurrence of a large temperature rise in a part of the electrical connection unitand/or the increase in thermal interference with the electronic component. As a result, it is possible to improve the thermal characteristics (for example, the heat dissipation property or the heat storage property) of the electrical connection unitwhile suppressing the increase in the number of components of the electrical connection unit.

3 93 2 92 93 1 In the present embodiment, the width Wof the heat storage portionin the Y direction is larger than the width Wof the base portionin the Y direction. According to such a constitution, it is easy to secure a large heat capacity in the heat storage portion. In this structure, the thermal characteristics of the electrical connection unitcan be further improved.

3 93 2 92 93 1 In the present embodiment, a thickness Tof the heat storage portionin the Z direction is larger than a thickness Tof the base portionin the Z direction. According to such a constitution, it is easy to secure a large heat capacity in the heat storage portion. Therefore, the thermal characteristics of the electrical connection unitcan be further improved.

93 93 1 In the present embodiment, the heat storage portionhas an outer shape different from a regular circle and a regular polygon when viewed from the Z direction. According to such a constitution, it is easy to secure a large heat capacity in the heat storage portionwithin a limited disposition area. Therefore, the thermal characteristics of the electrical connection unitcan be further improved.

41 88 93 88 88 88 88 93 88 93 88 93 92 93 1 a b a b In the present embodiment, the base memberT includes a holding portionthat holds the heat storage portion. The holding portionincludes the first portionand the second portion. The first portionis located between the first member and the heat storage portionin the Z direction. The second portionfaces the heat storage portionin the Y direction. According to such a constitution, the holding portionthat holds the heat storage portionis obtained by using the difference in thickness between the base portionand the heat storage portion. According to this structure, it is easy to improve the durability (for example, impact resistance) and the like of the electrical connection unit.

1 110 120 110 93 120 93 110 90 110 1 In the present embodiment, the electrical connection unitincludes the metal plateand the heat transfer member. The metal platefaces the heat storage portionfrom a side opposite to the first member and the second member. The heat transfer memberis disposed between the heat storage portionand the metal plate. According to such a structure, heat transferred from the first member or the second member to the fastening memberis easily released to the outside through the metal plate. According to this structure, it is possible to further improve the thermal characteristics of the electrical connection unit.

90 90 90 90 13 10 42 42 90 44 90 90 90 90 90 1 a b a h h a b a b b In the present embodiment, the fastening memberhas the first portionand the second portion. The first portionis inserted into the first attachment hole and the second attachment hole in a state in which the first attachment hole (for example, the attachment hole) of the first member (for example, the electronic component) and the second attachment hole (for example, the attachment hole) of the second member (for example, the bus bar) overlap each other in the first direction (Z direction). The first portionhas the screw thread Sc and is engaged with a nut (for example, the engagement member). The width of the second portionin the X direction or the Y direction is larger than that of the first portion. The second portionfaces the first member or the second member in the Z direction. The second portionhas a volume twice or more the volume of the nut. According to such a constitution, it is easy to secure a large heat capacity in the fastening member. With this structure, the thermal characteristics of the electrical connection unitcan be further improved.

90 130 Next, a second embodiment will be described. The second embodiment is different from the first embodiment in that a fastening memberis attached to a connection component. Constitutions other than that described below are the same as the constitutions of the first embodiment.

18 FIG. 1 10 10 10 10 10 10 10 is a partially exploded perspective view illustrating a subunit SUT of the second embodiment. In the present embodiment, the electrical connection unitincludes a first electronic componentA and a second electronic componentB as a plurality of electronic components. The first electronic componentA and the second electronic componentB may be the same type of electronic component, or may be different types of electronic components.

1 130 130 10 42 10 42 130 10 10 42 130 42 130 130 131 132 133 In the present embodiment, the electrical connection unithas a connection component. The connection componentis a member that is disposed between the electronic componentand the bus barand connects the electronic componentto the bus bar. In the present embodiment, the connection componentis a connection component that connects a plurality of electronic components (for example, electronic componentsA andB) to one bus bar. In the present embodiment, the connection componentis an example of a “first member”. The bus baris an example of a “second member”. The connection componentis made of metal (for example, made of copper, made of a copper alloy, made of aluminum, or made of an aluminum alloy). The connection componentincludes, for example, a first portion, a second portion, and a third portion.

131 13 10 131 131 13 10 131 131 13 13 10 131 13 10 43 13 131 44 43 h h h h The first portionis a portion physically and electrically connected to the terminalof the first electronic componentA. The first portionis, for example, a plate portion provided in the horizontal direction. The first portionfaces the terminalof the first electronic componentA in the Z direction. The first portionhas an attachment holefacing the attachment holeof the terminalof the first electronic componentA. The first portionis fixed to the terminalof the first electronic componentA by, for example, a fastening memberpassing through the attachment holeand the attachment hole, and an engagement memberengaged with the fastening member.

132 13 10 132 132 13 10 132 132 13 13 10 132 13 10 43 13 132 44 43 h h h h The second portionis a portion physically and electrically connected to the terminalof the second electronic componentB. The second portionis, for example, a plate portion provided in the horizontal direction. The second portionfaces the terminalof the second electronic componentB in the Z direction. The second portionhas an attachment holefacing the attachment holeof the terminalof the second electronic componentB. The second portionis fixed to the terminalof the second electronic componentB by, for example, the fastening memberpassing through the attachment holeand the attachment holeand the engagement memberengaged with the fastening member.

133 131 132 90 133 133 131 132 133 133 42 42 133 133 130 133 91 90 133 133 42 42 h h h h h h h h The third portionis a portion that couples the first portionand the second portionand is physically and electrically connected to the fastening member. The third portionis, for example, a plate portion provided in the horizontal direction. The third portionis provided between the first portionand the second portion. The third portionhas an attachment holefacing the attachment holeof the bus bar. An inner circumferential surface of the attachment holedoes not have, for example, a screw groove. The attachment holeis a through-hole penetrating the connection componentin the Z direction. However, the attachment holemay be a hole having a screw groove and engaged with the shaftof the fastening member. The attachment holemay be a bottomed hole. In the present embodiment, the attachment holeis an example of a “first attachment hole”. The attachment holeof bus baris an example of a “second attachment hole”.

91 90 133 130 42 42 133 130 42 42 90 10 10 130 h h h h In the present embodiment, the shaftof the fastening memberis inserted into the attachment holeof the connection componentand the attachment holeof the bus barin a state in which the attachment holeof the connection componentand the attachment holeof the bus baroverlap each other in the Z direction. The fastening memberis thermally connected to the plurality of electronic componentsA andB via the connection component.

90 111 110 120 90 10 111 110 In the present embodiment, the fastening memberis thermally connected to the flat surface portionof the metal platevia the heat transfer memberas in the first embodiment. For example, the fastening memberalso functions as a heat transfer portion that collectively transfers part of heat generated by the plurality of electronic componentsto the flat surface portionof the metal plate.

10 10 90 1 According to such a constitution, the temperature rise of the plurality of electronic componentsA andB can be suppressed by one fastening member. Through this operation, the electrical characteristics of the electrical connection unitcan be improved.

140 Next, a third embodiment will be described. The third embodiment is different from the first embodiment in that an additional heat storage memberis provided.

The constitution other than that described below is the same as that of the first embodiment.

19 FIG. 20 FIG. 140 140 90 13 10 140 140 140 141 142 is a perspective view illustrating a part of a subunit SUT of the third embodiment.is a partially exploded perspective view illustrating the subunit SUT of the third embodiment. In the present embodiment, the subunit SUT has an additional heat storage memberin addition to the constitution of the first embodiment. The heat storage memberis disposed on a side opposite to the fastening memberwith respect to the terminalof the electronic component. The heat storage memberis made of metal (for example, made of copper, made of a copper alloy, made of aluminum, or made of an aluminum alloy). The heat storage membermay be referred to as a “metal member”. The heat storage memberincludes a blockand a hole.

21 FIG. 141 41 141 1 91 90 41 141 1 91 90 is a cross-sectional view illustrating the subunit SUT of the third embodiment. The blockis a metal portion having a rectangular parallelepiped outer shape. A height Hof the blockin the Z direction is larger than, for example, a half of a length Lof the shaftof the fastening memberin the Z direction. The height Hof the blockin the Z direction is larger than the length Lof the shaftof the fastening memberin the Z direction, for example.

142 141 142 142 142 44 45 142 141 141 141 a b. The holeis provided in the block. The holeis a cylindrical hole extending in the Z direction. The holeis open in the +Z direction. The diameter of the holeis larger than that of each of the engagement memberand the washer. By providing the hole, the blockhas a bottom portionand a peripheral wall portion

141 141 13 10 141 13 10 141 140 13 13 10 a a a a h h The bottom portionis a plate portion provided in the horizontal direction. The bottom portionfaces the terminalof the electronic componentin the Z direction. For example, the bottom portionis placed on the terminalof the electronic componentfrom the +Z direction side. The bottom portionhas an attachment holefacing the attachment holeof the terminalof the electronic component.

140 140 141 140 91 90 140 141 141 141 142 141 91 90 h h a h h b a b b An inner circumferential surface of the attachment holedoes not have, for example, a screw groove. The attachment holeis a through-hole penetrating the bottom portionin the Z direction. However, the attachment holemay be a hole having a screw groove and engaged with the shaftof the fastening member. The attachment holemay be a bottomed hole that is open in the −Z direction. The peripheral wall portionstands in the +Z direction from the bottom portion. The peripheral wall portionsurrounds the periphery of the hole. The peripheral wall portionextends, for example, toward the +Z direction side beyond the end on the +Z direction side of the shaftof the fastening member.

91 90 42 13 140 42 42 13 10 140 140 45 91 42 13 140 44 42 13 10 140 h h h h h h h h h In the present embodiment, the shaftof the fastening memberis inserted into the attachment holes,, andin a state in which the attachment holeof the bus bar, the attachment holeof the electronic component, and the attachment holeof the heat storage memberoverlap each other in the Z direction. The washerpasses through the tip of the shaftthat has passed through the attachment holes,, and, and is engaged with the engagement member. With this constitution, the bus bar, the terminalof the electronic component, and the heat storage memberare integrally fixed.

1 140 According to such a constitution, it is possible to further improve the thermal characteristics of the electrical connection unitby providing the additional heat storage member.

90 10 20 Next, a fourth embodiment will be described. The fourth embodiment is different from the first embodiment in that a fastening memberthat fastens an electronic componentto a connection componentis provided. The constitution other than that described below is the same as that of the first embodiment.

22 FIG. 1 90 71 91 90 13 10 21 20 13 10 21 20 91 90 13 10 10 20 h h h h h is a cross-sectional view illustrating a subunit SUS of the fourth embodiment. In the present embodiment, the electrical connection unitincludes a fastening memberinstead of the fastening memberdescribed above. The shaftof the fastening memberis inserted into the attachment holeof the electronic componentS and the attachment holeof the connection componentin a state in which the attachment holeof the electronic componentS and the attachment holeof the connection componentoverlap each other. In the present embodiment, the shaftof the fastening memberis engaged with the attachment holeof the electronic componentS. As a result, the electronic componentS and the connection componentare fixed.

90 10 20 1 1 According to such a constitution, by providing the fastening memberfastening the electronic componentS to the connection component, it is possible to further improve the thermal characteristics of the electrical connection unitwhile suppressing an increase in the number of components of the electrical connection unit.

Several embodiments and modification examples have been described above. However, the embodiment and the modification examples are not limited to the examples described above. For example, the plurality of embodiments and modification examples described above may be implemented in combination with each other.

1 Electrical connection unit SU, SUS, SUT Subunit 10 10 10 10 10 ,S,T,TA,TB Electronic component 13 13 13 ,A,B Terminal 13 h Attachment hole 20 Connection component 40 S Routing board 40T Routing structure 41 S Base plate 41 T Base member 42 Bus bar 42 h Attachment hole 90 Fastening member 90 a First portion 90 b Second portion 91 Shaft 92 Base portion 93 Heat storage portion 110 Metal plate (heat dissipation member) 120 Heat transfer member 130 Connection component 133 h Attachment hole